Problem with wrapping and terminal input

[WembleyFord2]

Issue Description

I am experiencing a problem with the terminal when it reaches the bottom of the terminal windows, wrapping breaks. For instance, if I type a series of characters longer than the line it wraps as one would expect and left and right cursor movements work as expected.

If the cursor gets to the last time of the window, then the behaviour breaks down. For instance, the cursor no longer moves up and down between the current line and the previous one.

And using backspace to delete characters from the upper part of the line causes even more distortion.

I've tested this on a clean installation of Ubuntu 18.04 with the latest Powershell, Code and Powershell Extension (and also the Preview extention). My LANG is set to en-GB.UTF-8. There are no problems with pwsh running from within bash on an xterm or Gnome Terminal or any other terminal, and there are no problems with the bash terminal in Core.

Any advice would be very welcome. This is making development work of PS scripts a real problem.

Environment Information

Visual Studio Code

Name	Version
Operating System	Linux x64 4.15.0-65-generic
VSCode	1.39.2
PowerShell Extension Version	2019.9.0

PowerShell Information

Name	Value
PSVersion	6.2.3
PSEdition	Core
GitCommitId	6.2.3
OS	Linux 4.15.0-65-generic %2374-Ubuntu SMP Tue Sep 17 17:06:04 UTC 2019
Platform	Unix
PSCompatibleVersions	1.0 2.0 3.0 4.0 5.0 5.1.10032.0 6.2.3
PSRemotingProtocolVersion	2.3
SerializationVersion	1.1.0.1
WSManStackVersion	3.0

Visual Studio Code Extensions

Visual Studio Code Extensions(Click to Expand)

Extension	Author	Version
bash-debug	rogalmic	0.3.6
csharp	ms-vscode	1.21.5
partial-diff	ryu1kn	1.4.0
perl-debug	mortenhenriksen	0.6.3
perl-toolbox	d9705996	1.3.2
powershell	ms-vscode	2019.9.0
prettier-vscode	esbenp	2.3.0
printcode	nobuhito	3.0.0
puppet-vscode	jpogran	0.21.0
vscode-emacs-friendly	lfs	0.9.0

[SydneyhSmith]

@WembleyFord2 thanks for opening this issue and providing detailed information...PSReadLine provides some of the code wrapping behavior and so having it enabled may resolve this issue...can you confirm that in your VSCode settings you have "powershell.developer.featureFlags": ["PSReadLine"], (note that this will only help if you are also using the PowerShell Preview extension). Please let us know if you are still running into this issue even with PSReadLine enabled...thanks!

[WembleyFord2]

Thanks for that suggestion - it does seem to have cured the problem. I did not have any powershell.developer.featureFlags line in the settings .json file - adding it in with PSReadLine did fix the issue. I must admit I am curious as to why this is broken out of the box and no-else seems to have noticed it.

[TylerLeonhardt]

Just fair warning, the PSReadLine experience isn't the best on PowerShell 6... We highly recommend using PowerShell 7 (which is in preview) for a much nicer experience.

[gwojan]

@TylerLeonhardt Just curious, but what's different in PowerShell 7 that makes the PSReadLine experience better?

[TylerLeonhardt]

@gwojan PowerShell 7 moved to .NET Core 3.0. In .NET Core 3.0, the completely redid the System.Console APIs. In that change, the made the PowerShell Integrated Console experience much more stable and "what you would expect".

For example,

• scrolling up works in PS 7 (not in PS 6, where it jumps back down to the bottom of the screen)
• the sudo command (or any other command that prompts) doesn't time out immediately

and a few other small details.

We feel that it's not worth it to put in the engineering effort to fix this for PowerShell 6 as that will go EOL 6 months after PowerShell 7's release (which is around when we will be shipping this PSRL stuff into stable).

[SydneyhSmith]

@WembleyFord2 glad to hear that resolved the issue for you, I will close this as a duplicate as PSReadLine, with a feature flag, is available in the PowerShell Preview extension, and we are tracking that PSReadLine is not available in the main PowerShell Extension here #1793